Controllable fabrication of Au-nanoprotrusion arrays as a platform for the materials design and characterization

In Situ Transmission Electron Microscopy Observation of Electrochemical Process Between Li–C Nanocomposites and Multilayer Graphene

“…As described above (see also Figure 2), the Li–C film was characterized by metallic and oxide Li embedded in the amorphous C matrix. Agreeing well with our previous observation, [ 9 ] metallic Li was still preserved even after the film was exposed to air for the transfer to the TEM without using any transfer vessel or glovebox.…”

“…A detailed explanation of the experimental setup and a characterization of the AuNPs are reported elsewhere. [ 9a ] In brief, a graphite plate serving as a carbon supply source to enhance the formation of conical protrusions was positioned perpendicularly next to an Au foil substrate with its 10 × 0.05 mm 2 thin edge facing upward. Ar + ion bombardment was done at 600 eV at an incident angle of 45° with respect to the Au substrate for 30 min at the basal and working pressures of 5.0 × 10 −4 and 5.0 × 10 −2 Pa, respectively.…”

“…The details of the Li–C film deposition and a characterization are described elsewhere. [ 9 ] Briefly, a graphite plate with Li shots served as the target, and was sputtered with Ar + ions at 700 eV for 30 min at basal and working pressures of 5.0 × 10 −4 and 5.0 × 10 −2 Pa, respectively. Figure 2b illustrates the SEM observation result of the AuNPs after the Li–C deposition.…”

“…In previous papers, we have demonstrated a Li–C nanocomposite prepared by an ion‐beam deposition method as a candidate electrode active material for lithium‐ion batteries (LIBs) with safer and easier handling. [ 9 ] In this newly developed Li–C nanocomposite, the metallic Li was preserved along with the Li oxide in the amorphous carbon matrix even after air exposure, without using any transfer vessel or glovebox. [ 9 ] We have also showed that Au nanoprotrusions (AuNPs) are ready to use as a convenient platform for TEM in a cross‐sectional‐like mode.…”

“…[ 9 ] In this newly developed Li–C nanocomposite, the metallic Li was preserved along with the Li oxide in the amorphous carbon matrix even after air exposure, without using any transfer vessel or glovebox. [ 9 ] We have also showed that Au nanoprotrusions (AuNPs) are ready to use as a convenient platform for TEM in a cross‐sectional‐like mode. [ 9a ] In this paper, by combining both components together with graphene layers synthesized on a W probe, we have attempted the real‐time visualization of the electrochemical reactions of the metallic Li embedded in the Li–C nanocomposite during the battery discharge process, using in situ TEM.…”